Voltar
Artigo Acesso aberto Produção Nacional Revisado por pares
BIBTEX RIS

Immunization against the colonization factor antigen I of enterotoxigenic Escherichia coli by administration of a bivalent Salmonella typhimurium aroA strain

1998; Associação Brasileira de Divulgação Científica; Volume: 31; Issue: 4 Linguagem: Inglês

10.1590/s0100-879x1998000400012

ISSN

1414-431X

Autores

Heloisa Guillobel, M.G. Luna, Erwin Camacho, Darcy F. de Almeida, Luís Carlos de Souza Ferreira,

Tópico(s)

Viral gastroenteritis research and epidemiology

Resumo

An expression plasmid (pCFA-1) carrying the cfaB gene that codes for the enterotoxigenic Escherichia coli (ETEC) fimbrial adhesin colonization factor antigen I (CFA/I) subunit was constructed and used to transform a derivative of the attenuated Salmonella typhimurium aroA vaccine strain SL3261 carrying an F'lacIq. Treatment of the transformed strain with isopropyl-ß-D-thiogalactopyranoside (IPTG) resulted in elevated in vitro expression of the CFA/I subunit. Although flagellar function and lipopolysaccharide (LPS) synthesis were similar in both the parental and the recombinant strains, spleen colonization was reduced in the recombinant strain. All BALB/c mice parenterally inoculated with the recombinant strain developed significant anti-CFA/I and anti-LPS serum antibody titers (P 0.05) while 4/5 of the same mice developed anti-LPS IgA (P<0.05). The results indicate that the vaccine strain elicited an antibody response against the bacterial host both after oral and intravenous immunization while the response against the CFA/I antigen was significant only after inoculation by the intravenous route

Referência(s)